Trimming mechanism for sewing machines



April 16, 1935. J. P. wEls 1,998'l1 TRIMMING MECHANISM FOR SEWING MACHINES Filed Feb. 1s, 1934 ATToRNExy? Pnented Apr. 1e, 193s UNTTED lSTATES PATENT .OFFICE 1,998,111 'mamme MEcnANIsM'l-on SEWING a MACHINES John P. Weis, Nyack, N. Y., asslgnor to Metropolitan Sewing Machine Corporation, Nyack, I N. Y., a corporation of Delaware Y Application February 13, 1934, Serial No. 711,003

40 Claims.

'5 plished simultaneously, the object of the invenlil tion being to provide a pinking and trimming mechanism and an improved method by means of which a French felled seammay be produced simultaneously with the pinking of the free or raw edges thereof. i

A further object of the inventionr is the provision oi an improved rotary pinking or trimming means located below the working surface or cloth plate of the sewing machine over which the fabric passes during the stitching operation thereby not only leaving the work space entirely clear under the overhanging arm of the machine to permit the 4work to be freely handled but permitting also the stitching and tri". if.v Vv of a felled seam and, therefore, the trimming of the free edges of the work as it passes through the stitchv ing` mechanism.

AA further object of the invention wis the provision of an improved trimming or pinking mechanism so located under the cloth plate that it does not in any way interfere with or obstruct the'use of the machine for ordinary plain stitching and by reason of its location is always in readiness for use either for plain work or for pinking and seeming without the removal of any parts.

A further object of the invention isthe provision of a simple, inexpensive and'efilcient pinking mechanism readily applied to sewing-machines as a permanent attachment thereto and. so located as to avoid the necessity of detaching the same for plain stitching and which 'is also effective for making a felled seam and pinking the same.

Another Objectis the provision of an improved trimming or pinking mechanism adapted for use with the well knownMetropolitan sewing machines and operated from the regular feeding mechanism thereby to permit the pinking cutter to work in unison or be synchronized with and be regulated by the adjustable means provided for changing the strokeof the feed dog thereby to vary the length of the stitch.

This improved rotary pinking trimmer is operative adjacent to and co-operates with the fourmotion feed dog of such a sewing machine to trim the bottom ply of work, thus leaving the space free'under the arm for the handling of the work above the cloth plate when it is desired to plain stitch the work.

In the drawing accompanying and forming a part of this specification, Fig. 1 is a front view showing so much of thestitching and feeding mechanism of a well known Metropolitan sewing machine as is deemed necessary to illustrate the present improvement: 5

Fig. 2 is 'a detail, partly sectional view of this improved pinking mechanism applied to the machine: I

Fig. 3 is a perspective partly sectional view of the improved pinking attachment and illustrates lV the manner of making the felled seam:

Fig. l is an end view of the sewing machine illustrated in Fig. 1, looking in the direction of the arrow in Fig. l, and I Figs. 5 and 6 are detail views of the pinking 15 element and the work guard for covering the exposed edge of the pinking cutter. A

Similar characters of reference indicate corresponding parts in the several views.

Before explaining in detail the present iin-420 provement and mode of operation thereof, I desire to have it understood that the invention is not limited to the details of construction andl arrangement of parts illustrated in the accompanying drawing since the invention is capable of other embodiments, and that the phraseology which If employ is for the purpose of description and notof limitation.

The sewing machine illustrated has the usual machine base i having a left hand bearing 2 for 30. the main driving shaft 3. rIfhe rear end of the cloth plate 5 is supported by the lower portion l of the top arm, shown broken away, in the usual manner and the opposite end of the cloth plate is supported as at '6 by a projection 1 of the 35 looper bracket 8, this looper bracket being secured to the base of the machine in the usual way and.carrying the looper sh ft 9 operating in bearings III and II. /a

This looper bracket also has bearings I2, see 40 Fig. l, for the looper vibrating crank shaft I3 located transversely to the looper shaft 9 for imparting end-wise movement to the looper shaft 9 located in the bearings I0 and II.

Rocking motion is imparted to the looper shaft 9 by an eccentric I4 secured to the main shaft 3 through the medium of a connection I5 operating on the eccentric and connected by a screw I6 to a crank arm I1 secured as at I8 to the looper shaft 9. By'this means, movement is given to 50 the looper carrier I9 and looper 20 so that it will coact with the needle 2I to make the stitch. the looper and the needle being threaded in the usual way. It is to be derstood, however, that any of the well-known lock stitch mechanisms may be used in place of the thread carrying looper 20 and the well-known vertical hook of lock stitch machines or the high speed rotary hook-of the well-known Wilcox and Gibbs machine could be used in connection with the improved pinking and trimming mechanism herein shown and described.

The sewing machine illustrated herein has the usual top arm, not shown, terminating in a head, the lower portion only of which is shown in Fig. 4 and which head carries the usual presser foot shank 23 and a compensating presser foot 24. This presser foot is made in several parts so as to yield and compensate for different thicknesses of work. That is to say, if the character of work requires a seam composed of two or three thicknesses of material so that different portions of the work will be engaged by the presser foot, the sections 25 and 26 of the presser foot may be arranged to accommodate such varying thicknesses in the work. These compensating presser feet are well known in the art, it being a mere matter of selection to provide suitable presser feet for seams of varying thicknesses and the sections of the presser feet have independent pressure given to them by springs 21.

The main shaft 3 operating in the bearing 2 has an adjustable crank 28, see Fig. 4, operating a connection 29 connected as at 30 to atop of a feed rocker frame 3| pivoted to the base of the machine as at 32 in the usual way. This rocker frame operates the feed bar 33 to impart movement to the four-motion feed dog 34 loperating through the throat plate 35. This feed dog operates at the left of and in front of the needle 2|, see Fig. 3, and also extends in the rear of the needle and quite some distance to the right of the line of stitches made by the needle so as to act on the goods directly in back of the pinking cutter. The right hand extension of the rear portion of the feed coacts with the section 25 of the compensating presser foot while the left hand section of the feed 34 coacts with the compensating section 26 of the presser foot, the needle 2| co-operating with the looper 23 to form the stitches, this needle passing through the needle hole 36 in the throat plate 35, the work being acted upon by the feed dog 34 so as to draw it from the stitching position as illustrated in Fig. 3.

The cloth plate is provided on the under side thereof with bearings 31 and 38, see Fig. 2, for the reception of a shaft 39 having secured thereto the rotary pinking cutter 4|) shown of circular or disk form having a continuous set of cutting teeth to pink the work and which is driven by this shaft and is adjustable to and from the stitch line with the shaft in the bearings 31 and 38.

The intermittent clutch 4| is secured to the shaft by a screw 42, this clutch being located between the bearings 31 and 38 which thus prevents the shaft from shifting endwise except when the screw 42 is released and which thus permits lateral adjustment of the rotary trimming cutter when desired.

The clutch has an oscillating lmember 43 operated by a connection 44 which is loosely connected as at 45 to this oscillating member so as to give a. step by step movement to the pinking cutter in unison with the feed dog 34.

The opposite end of this connection or connector 44 is secured as at 45, see Fig. 4, to a segmental lever or member 46, likewise mounted on the pivot shaft 32 and is rocked back and forth by a connection 41, one en d of which is coupled to the top end of the segmenetal lever 46 and the opposite end being connected with an eccentric mounted on the shaft 3 whereby a rocking motion is imparted to this segmental lever so as to operate the connection 44 and thereby the intermittent clutch to rotate the rotary pinking cutter.

By adjusting an end of the connection 44 to diierent positions on the segmental lever, the oscillating movement of the clutch member 43 is regulated to vary the stroke of the pinking cutter independently of the stroke of the feed dog and since the pinking cutter is very efcient in feeding the work it is often advantageous to give it a greater or less stroke on different kinds of Work thereby to overcome stretching in some instances and at other times to cause the work to feed somewhat in a curved path to the right or left as the case may be which is an advantage in stitching curved or circular work.

There are many kinds of stitching operations in which such a differential movement of the pinking cutter relative to the four-motion feed would not be required and in these operations the connecting link or connector 44 could be secured directly to the feed operating parts so that the change in the stroke of the feed dog would also change the stroke of the pinking cutter, in which case, the segmental lever 46 would not be required.

Coacting with the pinking cutter 40 is a hardened steel member 49 which overhangs the top surface of the cutting edge of the pinking cutter. This hardened member is slightly rounded upward at its front edge as at 5|| to facilitate the passage of the work therebetween and the cutter, and downward at its rear projecting edge as at 5| to facilitate the passage of that particular part of the work passing over the plate back to its normal position relative to the other portion of the work. The overhang or projection of this member is made to suit variations in width of seam according to requirements.

To give pressure to this member against the cutting surface of the pinking cutter 40, an adjusting means in the form of a pin 52, see Fig. 3 is provided, this pin being located in a small recess in the top surface of the cloth plate 5 and is in alignment with the main driving shaft 3 and therefore at right angles to the line of stitching.

This pin supports the fixed cutting member or plate 49 which is a part of and projects from the left hand edge of a plate 56. The adjusting screw 54 holds this plate 56 securely to'the cloth plate 5 at the rear of the pin 52 while two screws 55 hold the front edge of this plate in fixed relation to the cloth plate in front of the pin 52. This pin 52 forms a rocking member upon which the plate 56 rests and rocks and by reason of the adjusting screws, it may be tipped toward or from the pinking cutter 40 and located in such position by the `tightening of the screws 54 and 55 and as the pin 52 is seated in the cloth plate and also in a recess in the plate 56 carrying the cutting member 49, this affords one way of securing that cutting member 49 in an adjustable manner with relation to the rotary cutter 40. In other words, this pin 52 provides suiiicent space between the top surface of the cloth plate 5 and the bottom surface of the plate `56 to permit adjustment of the plate 56 and the rigid or stationary hardened plate 49 in the manner just described and the space thus provided between the cloth plate and the hardened steel portion 49 of the plate 56 would provide in part accommodation for the inediti range of work for which the machine is to be used. That is to say, if the cutter 4B projected over the cloth plate one-eighth of an inch and the cutting member 49 were brought into contact with the cutter, goods equal to the thickness of approximately one-eighth of an inch would pass through the machine freely.

YIb-acconimodate seams and other obstructions, this space would have to be three-sixteenths or one-fourth of an inch as the case may be, the object, however, being to confine this space, 'especially for thin delicatesilk fabrics so that portions of a garment being seamed may be fed over the top of the plate 56 with the least possible resistance.

When the machine is equipped for heavier work and greater space is required forthe seams to pass through, the adjustment of the plate 56 would elevate it suciently to accommodate such extra thicknesses.

Secured to the front edge of the plate S is a shank 51 of a work guide 58 which has a projecting end 5S, see Fig. 3, located in line with Ythe line of stitches and positioned very close to the front of the needle hole 35. This guide has elongated slots and may be adjusted by means of the screws 60 and 6i so as to properly control the folded edge 62 of the goods or work 63 folded around this guide, the free edge 65 of the work being pinked by the cutter 4t.

This free edge is fed in under the guide et and on top of the free edge 56 of the fabric dll. In other words, the two pieces of fabric, the right hand piece B3 and the left hand piece Si are fed together over the top of the cloth plate with the inner edge of the fabric @3 folded under and around the guide 58 on top of the projecting edge of the fabric Gl, the two pieces of fabric being stitched by the stitching mecha to form the seam. These lapping edges of the fabric to be pinked will pam under the hardened steel portion of the plate 56 and between it and the rotary trimming cutter d@ and thus pinked.

It will be obvious that by adjust .lthe screws 6B and SI of the folder guide 58, teprper fold 62 will be made in the edge of the right hand piece of fabric @3, thus fo a felled seam. 'This folder guide is adjustable to control the margin from the stitch line. Thus, by means of this improved trg mechanism, a French felled seam can be simultaneously made and pinked from the under side since the free projecting edges 65 and BS of the two layers of material may be readily pinked without pinking through the overlapping top layer t3 of the work by reason of the means hereinbefore referred to that separates such projecting or free edges from the overlapping portion of the material.

Whe' the machine is to be used for plain or ordinary stitching and no trimming is required, a suitable guard t8, see Figs. 5 and 6 is adjustable in the manner shown in Fig. 6 so that the guard will contact with the edge" of the hardened .plate 4i and' thus cause the work to feed up over the member 5! instead of thereunder and prevent it from getting into cutting position between the hardened member 49 and the rotary cutter Il.

- When it is desired to pink the work, the screw a rotary disk shaped trimmer located below said 6 9 is loosened and the guard shifted to the position shown rin Fig. 5 thereby permitting the edge to be pinked to be fed between the hardened plate 49 and the cutter 40.

This guard has a collar 'l0 which fits over the hub 'Il of the bearing 31 and the semi-circular portion 12 of the guard guards the cutting surface of the cutter and protects the ers of the operator, and thus it will seen that this guard serves two purposes in that it at all times pro-l tects the operator from injury by the cutter 40 and is adjustable to close the opening between the cutting members when adjusted as shown in- ,plies of a piece of work having free edges and which trimming mechanism is eective to permit plain work or pinking work without the dey tachment or attachment thereof or the removal or replacement of any parts.

Itis to be understood that, by describing in detail herein any particular form', structure or arrangement, it is not intended to limit the invention beyond the terms of the several cl or the requirements of the prior art.

Having thus explained the nature of my said invention and described a way of constructing and using the same, although without attempting to set forth all of the forms in which it may be made, or all of the modes of its use, I claim:

l. .A trg attachment pted for use with a sewing machine and comprising a rotary disk shaped trimmer, means for rotating it, and a stationary hardened surface located above the rotary trimmer and co-operating therewith.

2. A trimming attacent adapted for use with a sewing machine and comprising a rotary disk shaped trimmer, means for rotating it, and a stationary hardened adjustable surface located above the rotary ter and co-operating therewith.

3. A trimming attachment adapted for with a sewing machine having stitching mechanism including a needle and comprising a rotary trimmer, means for operating it, a stationary hardened surface located above the rotary trimmer and cai-operating therewith, and means for adjusting the trimmer toward and from the needle.

,4. A trimming attachment adapted for use with a sewing machine having stitching mechanism including a needle and comprising a rotary trimmer, means for operating it, a stationary hardened surface located above the rotary trimmer and co-operating therewith, means for adjusting the trimmer toward and from the needle,

and means for adjusting the hardened surfaw toward and from the trimmer.

5. In a sewing machine having a cloth plate,v

cloth plate, a rigid co-operating surface above said plate, feeding mechanism, and means operative simultaneously with the feeding mechanism for operating said trimmer.

8. In a sewing machine, having a cloth plate,

a rotary trimmer located below said cloth plate,

a rigid co-operating surface above said plate, means for operating the rotary trimmer, and means for regulating the speed of the rotary trimmer.

9. In a sewing machine having a cloth plate, a rotary trimmer located below said cloth plate, a rigid co-operating surface above Said plate, meansgfor operating the rotary trimmer, feeding mechanism, and means connected with the feed mechanism for regulating the speed of the rotary trimmer.

10. In a sewing machine having a cloth plate, aA rotary trimmer located below said cloth plate,

a rigid co-operating surface above said plate,

means for operating the rotary trimmer, and oscillating means for regulating the feed of the rotary trimmer.

11. In a sewing machine having a cloth plate, a rotary trimmer located below said cloth plate, a rigid co-operating surface above said plate, eccentrically operated means for operating the trimmer, and means for regulating the speed thereof.

12. A -sewing machine having a cloth plate, a rotary pinking trimmer supported below said plate and projecting therethrough, and means for rotating it.

13. A trimming attachment for sewing machines having a cloth plate and comprising a rotary disk shaped trimmer supported under and projecting through said plate, means for rotating it, a stationary rigidly supported co-operating hardened member located above said plate, and means for rigidly supporting the ro- -tary trimmer in position to co-operate with said member.

14. A trimming attachment for sewing machines having a cloth plate and comprising a rotary trimmer supported under and projecting through said plate, means for rotating it, a stationary rigidly supported co-operating hardened member located above said plate, means for rigidly supporting the rotary trimmer in position to co-operate with said member, and means for adjusting said hardened member toward and from the rotary trimmer.

15. A trimming attachment for sewing machines having stitching means and comprising a rotary pinking trimmer, means for rotating it, and means co-operating therewith, said rotary trimmer and its co-operating means being so located as to pink the bottom plys of a felled seam during the stitching thereof.

16. A trimming attachment. for sewing ma- .chines having stitching means and comprising a rotary pinking trimmer, means for rotating it,

mer and its co-operating means being so located as to pink. the bottom plys of a felled seam during the stitching thereof, and means operative to feed a part of the work between the trimming members and a part thereof over the co-operating member. l

17. A trimming attachment for sewing machines having stitching means and comprising a chines comprising a rotary cutter, means for rotating it, a stationary rigidly supported cooperating hardened plate located above said rotary cutter, and means for regulating the pressure of said plate relative to the rotary cutter.

19. A trimming mechanism for sewing machines comprising a rotary cutter, means for rotating it, a stationary rigidly supported cooperating hardened plate located above said rotary cutter, and means for regulating the pressure of said plate relative to the rotary cutter and including means for supporting said plate for rocking movement.

20. A trimming mechanism for sewing machineshaving a cloth plate and comprising a rotary trimmer supported below the cloth plate, means for rotating it, a stationary rigidly supported co-operating hardened member located above the cloth plate, and an adjustable protecting guard adjustable into position to guide the folded edge of the work between the cutting members or thereabove.

21. A sewing machine having a cloth plate, a diskV shaped rotary cutter projecting through the plate from the underside thereof, means for rotating it, and means for varying the speed thereof.

22. A sewing machine having a cloth plate, a disk shaped rotary cutter projecting through the plate from the under side thereof, means for rotating it intermittently, and means for varying the speed thereof.

23. A sewing machine having a cloth plate, a disk shaped rotary cutter projecting through the plate from the under side thereof, feed mechanism, and means for operating the cutter coincident with the feed mechanism.

24. A sewing machine having a cloth plate, a disk shaped rotary cutter projecting through the plate from the under side thereof feed mechanism, and means for operating the cutter eoincident with the feed mechanism and including means for varying the speed thereof.

25. A sewing machine having a disk shaped rotary cutter, means for rotating it, a xed member co-operating therewith, and a shiftable member to guide the work between said members or over the xed member.

26. A sewing machine having a disk shaped rotary cutter, means for rotating it, a iixed member co-operating therewith, and a shiftable member to guide the work between said members o'r over the xed member and comprising a guard for the cutter.

27. A sewing machine having a disk shaped rotary cutter, means for rotating it, a fixed member co-operating therewith, and a shiftable member to guide the work between said members or over the xed member and comprising a guard for the cutter and means for securing it in any of its adjusted positions.

28. A sewing machine having a cloth plate, a driving shaft, a shaft located below the cloth plate, a disk shaped rotary pinking cutter carried by said last shaft and projecting through the plate, means connected with the driving shaft for operating the cutter, and rigid means located above the cutter for co-operation therewith.

29. A sewing machine having a cloth plate, a driving shaft, a shaft located below the cloth plate, a disk shaped rotary cutter carried by said last shaft and projecting through the plate.. means connected with the driving shaft for operating the cutter, rigid means located abov" the cutter for co-operation therewith, and means for regulating the speed of the cutter.

30. A sewing machine having a cloth plate, a driving shaft, a shaft located below the cloth plate, a. disk shaped rotary cutter carried by said last shaft and projecting through the plate, eccentric means connected with the driving shaft for operating the cutter, rigid means located above the cutter for co-operation therewith, and means for regulating the speed of the cutter.

31. A sewing machine having a cloth plate, a driving shaft, a shaft located below the plate, a disk shaped rotary pinking cutter carriedby said last shaft and projecting through the plate, feed mechanism, means connected with the driving shaft for operating the feed mechanism, means also connected with the driving shaft for rotating the cutter, and fixed means located above the cutter and co-operating therewith.

32. A sewing machine having a cloth plate, a driving shaft, a shaft located below the plate, a disk shaped rotary cutter carried by said last shaft and projecting through the plate, feed mechanism, means connected with `the driving shaft for operating the feed mechanism, means also connected with the driving shaft for rotating the cutter, fixed means located above the` cutter and co-operating therewith, and means for regulating the speed of the cutter according to the speed of the feed mechanism.

33. A sewing machine having a cloth plate, a driving shaft, a shaft located below the cloth plate, a rotary cutter carried by said last shaft and projecting through the plate, a four-motion feed mechanism, a. shaft supporting said fourmotion feed mechanism, means connecting said feed shaft with the driving shaft for operating the feed mechanism, means also connecting said feed shaft with the driving shaft for intermittently rotating the cutter, and means located above the cutter and co-operating therewith.

34. The method of forming a felled seam which consists in hemming one layer of fabric and stitching the hemmed edge thereof to another layer of fabric along the top of the hemmed portion thereby to provide juxtaposed portions of said fabrics projecting beyond the stitch line, and simultaneously pinking the projecting edges from below the layer having the hemmed edge by a rotary pinking movement.

35. The method of forming a seam which consists in stitching a plurality of plies of material together to form a seam having one or more free edges and simultaneously with such stitching, pinking the free edge portions of the fabric from the under side of such fabric by a rotary pinking movement without pinking an overlapping top layer of the work.

36. The method of forming a seam which consists in stitching a plurality of plies of material together to form a seam having one or more free edges and simultaneously with such stitching pinking the free edge portions of the fabric while lying in the normal horizontal plane of the ma'- terial being stitched from the under side of such fabric Without pinking an overlapping top layer of the work.

37. The method of forming a felled seam which consists in hemming one layer of fabric and stitching the hemmed edge thereof to another layer of fabric along the top of the hemmed portion thereby to provide juxtaposed portions of said fabrics projecting beyond the stitch line, and simultaneously pinking the projecting edges while lying in the normal horizontal plane of the `material being stitched from below the layer having the hemmed edge without pinking an overlappingtop layer of the work.

38. The method of forming a seam which consists in stitching a plurality of plies of material together to form a seam having one or more free edges and simultaneously with such stitching feeding the work between a hardened stationary surface and a movable pinking surface to effect the pinking of the work while lying in the normal horizontal plane of the material being stitched.

39. The method of forming a seam which consists in stitching a plurality of plies of material together to form a seam having one or more freeedges and simultaneously with such stitching feeding the work between a hardened stationary surface and a movable pinking surface below said stationary surface to effect pinking of the work from the underside thereof.

40. The method of forming a seam which consists in stitching a plurality of plies of material together to form a seam having one or more free edges and simultaneously with such stitching feeding the work between a hardened stationary surface and a rotary pinking surface synchronized with the feeding of the work to effect the pinking of such work. .y

` JOHN P. WEIS. 

